Dhupguri, Sept. 1: Chief minister Buddhadeb Bhattacharjee today asked Bhutan to make “sincere’’ efforts to flush out Kamtapuri Liberation Organisation militants hiding in that country and said he would soon visit Thimpu to discuss the issue with the Bhutanese king.

“KLO and its ally Ulfa have been carrying out subversive activities in north Bengal from their safe havens in south Bhutan. We cannot tolerate it any longer. I will personally take up the matter with the Bhutanese king,” Bhattacharjee, on his first visit to Dhupguri since the KLO gunned down five party workers on August 17, said at a party rally held under tight security.